enhancement: expose fetch as an srpmproc library component

cmd/srpmproc/fetch.go

@@ -21,16 +21,9 @@
 package main
 
 import (
-	"errors"
-	"fmt"
-	"github.com/rocky-linux/srpmproc/pkg/data"
+	"github.com/rocky-linux/srpmproc/pkg/srpmproc"
 	"github.com/spf13/cobra"
-	"io/ioutil"
 	"log"
-	"net/http"
-	"os"
-	"path/filepath"
-	"strings"
 )
 
 var fetch = &cobra.Command{
@@ -46,94 +39,10 @@ func init() {
 }
 
 func runFetch(_ *cobra.Command, _ []string) {
-	wd, err := os.Getwd()
+	err := srpmproc.Fetch(cdnUrl)
 	if err != nil {
 		log.Fatal(err)
 	}
-
-	metadataPath := ""
-	err = filepath.Walk(wd, func(path string, info os.FileInfo, err error) error {
-		if strings.HasSuffix(path, ".metadata") {
-			if metadataPath != "" {
-				return errors.New("multiple metadata files")
-			}
-			metadataPath = path
-		}
-		return nil
-	})
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	metadataFile, err := os.Open(metadataPath)
-	if err != nil {
-		log.Fatalf("could not open metadata file: %v", err)
-	}
-
-	fileBytes, err := ioutil.ReadAll(metadataFile)
-	if err != nil {
-		log.Fatalf("could not read metadata file: %v", err)
-	}
-
-	client := &http.Client{
-		Transport: &http.Transport{
-			DisableCompression: false,
-		},
-	}
-	fileContent := strings.Split(string(fileBytes), "\n")
-	for _, line := range fileContent {
-		if strings.TrimSpace(line) == "" {
-			continue
-		}
-
-		lineInfo := strings.Split(line, " ")
-		hash := lineInfo[0]
-		path := lineInfo[1]
-
-		url := fmt.Sprintf("%s/%s", cdnUrl, hash)
-		log.Printf("downloading %s", url)
-
-		req, err := http.NewRequest("GET", url, nil)
-		if err != nil {
-			log.Fatalf("could not create new http request: %v", err)
-		}
-		req.Header.Set("Accept-Encoding", "*")
-
-		resp, err := client.Do(req)
-		if err != nil {
-			log.Fatalf("could not download dist-git file: %v", err)
-		}
-
-		body, err := ioutil.ReadAll(resp.Body)
-		if err != nil {
-			log.Fatalf("could not read the whole dist-git file: %v", err)
-		}
-		err = resp.Body.Close()
-		if err != nil {
-			log.Fatalf("could not close body handle: %v", err)
-		}
-
-		hasher := data.CompareHash(body, hash)
-		if hasher == nil {
-			log.Fatal("checksum in metadata does not match dist-git file")
-		}
-
-		err = os.MkdirAll(filepath.Dir(path), 0755)
-		if err != nil {
-			log.Fatalf("could create all directories")
-		}
-
-		f, err := os.Create(path)
-		if err != nil {
-			log.Fatalf("could not open file pointer: %v", err)
-		}
-
-		_, err = f.Write(body)
-		if err != nil {
-			log.Fatalf("could not copy dist-git file to in-tree: %v", err)
-		}
-		_ = f.Close()
-	}
 }
 
 func init() {

pkg/srpmproc/fetch.go

@@ -0,0 +1,106 @@
+package srpmproc
+
+import (
+	"errors"
+	"fmt"
+	"github.com/rocky-linux/srpmproc/pkg/data"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+func Fetch(cdnUrl string) error {
+	wd, err := os.Getwd()
+	if err != nil {
+		return err
+	}
+
+	metadataPath := ""
+	err = filepath.Walk(wd, func(path string, info os.FileInfo, err error) error {
+		if strings.HasSuffix(path, ".metadata") {
+			if metadataPath != "" {
+				return errors.New("multiple metadata files")
+			}
+			metadataPath = path
+		}
+		return nil
+	})
+	if err != nil {
+		return err
+	}
+
+	metadataFile, err := os.Open(metadataPath)
+	if err != nil {
+		return fmt.Errorf("could not open metadata file: %v", err)
+	}
+
+	fileBytes, err := ioutil.ReadAll(metadataFile)
+	if err != nil {
+		return fmt.Errorf("could not read metadata file: %v", err)
+	}
+
+	client := &http.Client{
+		Transport: &http.Transport{
+			DisableCompression: false,
+		},
+	}
+	fileContent := strings.Split(string(fileBytes), "\n")
+	for _, line := range fileContent {
+		if strings.TrimSpace(line) == "" {
+			continue
+		}
+
+		lineInfo := strings.Split(line, " ")
+		hash := lineInfo[0]
+		path := lineInfo[1]
+
+		url := fmt.Sprintf("%s/%s", cdnUrl, hash)
+		log.Printf("downloading %s", url)
+
+		req, err := http.NewRequest("GET", url, nil)
+		if err != nil {
+			return fmt.Errorf("could not create new http request: %v", err)
+		}
+		req.Header.Set("Accept-Encoding", "*")
+
+		resp, err := client.Do(req)
+		if err != nil {
+			return fmt.Errorf("could not download dist-git file: %v", err)
+		}
+
+		body, err := ioutil.ReadAll(resp.Body)
+		if err != nil {
+			return fmt.Errorf("could not read the whole dist-git file: %v", err)
+		}
+		err = resp.Body.Close()
+		if err != nil {
+			return fmt.Errorf("could not close body handle: %v", err)
+		}
+
+		hasher := data.CompareHash(body, hash)
+		if hasher == nil {
+			log.Fatal("checksum in metadata does not match dist-git file")
+		}
+
+		err = os.MkdirAll(filepath.Dir(path), 0755)
+		if err != nil {
+			return fmt.Errorf("could create all directories")
+		}
+
+		f, err := os.Create(path)
+		if err != nil {
+			return fmt.Errorf("could not open file pointer: %v", err)
+		}
+
+		_, err = f.Write(body)
+		if err != nil {
+			return fmt.Errorf("could not copy dist-git file to in-tree: %v", err)
+		}
+		_ = f.Close()
+	}
+
+	return nil
+}